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1.
Holist Nurs Pract ; 37(4): E53-E58, 2023.
Article in English | MEDLINE | ID: mdl-37335152

ABSTRACT

The aim of this article is to elaborate on consolation management aesthetics in terms of literature, art, and music. This article will be centered on holistic nurses who come in daily contact with vulnerable patients in need of both medical treatment and consolation, as they continue their journey toward one or another outcome. Consolation management aesthetics enables the patients to shift their attention from something that appears intractable to something that motivates, bolsters existential resilience, and offers hope and optimism for the future. Holistic nursing aesthetics, involving psychological healing through literature, art, and music, can help anxious, troubled patients to once again find beauty and balance in their lives.


Subject(s)
Holistic Nursing , Humans , Anxiety , Esthetics
2.
Nature ; 540(7633): 453-457, 2016 12 15.
Article in English | MEDLINE | ID: mdl-27871088

ABSTRACT

Light-induced oxidation of water by photosystem II (PS II) in plants, algae and cyanobacteria has generated most of the dioxygen in the atmosphere. PS II, a membrane-bound multi-subunit pigment protein complex, couples the one-electron photochemistry at the reaction centre with the four-electron redox chemistry of water oxidation at the Mn4CaO5 cluster in the oxygen-evolving complex (OEC). Under illumination, the OEC cycles through five intermediate S-states (S0 to S4), in which S1 is the dark-stable state and S3 is the last semi-stable state before O-O bond formation and O2 evolution. A detailed understanding of the O-O bond formation mechanism remains a challenge, and will require elucidation of both the structures of the OEC in the different S-states and the binding of the two substrate waters to the catalytic site. Here we report the use of femtosecond pulses from an X-ray free electron laser (XFEL) to obtain damage-free, room temperature structures of dark-adapted (S1), two-flash illuminated (2F; S3-enriched), and ammonia-bound two-flash illuminated (2F-NH3; S3-enriched) PS II. Although the recent 1.95 Å resolution structure of PS II at cryogenic temperature using an XFEL provided a damage-free view of the S1 state, measurements at room temperature are required to study the structural landscape of proteins under functional conditions, and also for in situ advancement of the S-states. To investigate the water-binding site(s), ammonia, a water analogue, has been used as a marker, as it binds to the Mn4CaO5 cluster in the S2 and S3 states. Since the ammonia-bound OEC is active, the ammonia-binding Mn site is not a substrate water site. This approach, together with a comparison of the native dark and 2F states, is used to discriminate between proposed O-O bond formation mechanisms.


Subject(s)
Cyanobacteria/chemistry , Electrons , Lasers , Photosystem II Protein Complex/chemistry , Photosystem II Protein Complex/metabolism , Temperature , Ammonia/chemistry , Ammonia/metabolism , Bacterial Proteins/chemistry , Bacterial Proteins/metabolism , Binding Sites , Crystallization , Manganese/metabolism , Models, Molecular , Oxygen/metabolism , Substrate Specificity , Water/metabolism
3.
Proc Natl Acad Sci U S A ; 116(34): 16841-16846, 2019 08 20.
Article in English | MEDLINE | ID: mdl-31391299

ABSTRACT

Nature's water splitting cofactor passes through a series of catalytic intermediates (S0-S4) before O-O bond formation and O2 release. In the second last transition (S2 to S3) cofactor oxidation is coupled to water molecule binding to Mn1. It is this activated, water-enriched all MnIV form of the cofactor that goes on to form the O-O bond, after the next light-induced oxidation to S4 How cofactor activation proceeds remains an open question. Here, we report a so far not described intermediate (S3') in which cofactor oxidation has occurred without water insertion. This intermediate can be trapped in a significant fraction of centers (>50%) in (i) chemical-modified cofactors in which Ca2+ is exchanged with Sr2+; the Mn4O5Sr cofactor remains active, but the S2-S3 and S3-S0 transitions are slower than for the Mn4O5Ca cofactor; and (ii) upon addition of 3% vol/vol methanol; methanol is thought to act as a substrate water analog. The S3' electron paramagnetic resonance (EPR) signal is significantly broader than the untreated S3 signal (2.5 T vs. 1.5 T), indicating the cofactor still contains a 5-coordinate Mn ion, as seen in the preceding S2 state. Magnetic double resonance data extend these findings revealing the electronic connectivity of the S3' cofactor is similar to the high spin form of the preceding S2 state, which contains a cuboidal Mn3O4Ca unit tethered to an external, 5-coordinate Mn ion (Mn4). These results demonstrate that cofactor oxidation regulates water molecule insertion via binding to Mn4. The interaction of ammonia with the cofactor is also discussed.

4.
Biochim Biophys Acta ; 1857(1): 23-33, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26435390

ABSTRACT

Photosynthetic water oxidation to molecular oxygen is carried out by photosystem II (PSII) over a reaction cycle involving four photochemical steps that drive the oxygen-evolving complex through five redox states Si (i = 0,…, 4). For understanding the catalytic strategy of biological water oxidation it is important to elucidate the energetic landscape of PSII and in particular that of the final S4 → S0 transition. In this short-lived chemical step the four oxidizing equivalents accumulated in the preceding photochemical events are used up to form molecular oxygen, two protons are released and at least one substrate water molecule binds to the Mn4CaO5 cluster. In this study we probed the probability to form S4 from S0 and O2 by incubating YD-less PSII in the S0 state for 2­3 days in the presence of (18)O2 and H2(16)O. The absence of any measurable (16,18)O2 formation by water-exchange in the S4 state suggests that the S4 state is hardly ever populated. On the basis of a detailed analysis we determined that the equilibrium constant K of the S4 → S0 transition is larger than 1.0 × 10(7) so that this step is highly exergonic. We argue that this finding is consistent with current knowledge of the energetics of the S0 to S4 reactions, and that the high exergonicity is required for the kinetic efficiency of PSII.


Subject(s)
Oxygen/metabolism , Photosynthesis , Entropy , Oxidation-Reduction , Photosystem II Protein Complex/metabolism
5.
Int Arch Occup Environ Health ; 90(7): 703-711, 2017 10.
Article in English | MEDLINE | ID: mdl-28624972

ABSTRACT

PURPOSE: To investigate the relationships between symptoms compatible with the sick building syndrome (SBS) in adults and building dampness and ventilation in single-family houses. METHODS: Within the Swedish BETSI study, a national sample of single-family houses were inspected by professional building experts, and adults living in the houses answered a questionnaire on SBS. Relationships between building factors and SBS were analysed using logistic regression. RESULTS: Of the respondents, 23% reported having had weekly SBS symptoms during the last three months. A large proportion of houses exhibited building or construction problems. In total, 40% of houses had dampness problems in the foundation, and this was related to a higher prevalence of both mucous and dermal symptoms, and any SBS symptoms. Furthermore, high air humidity was related to more symptoms, with the relationship with absolute humidity being stronger than that with relative humidity or moisture load. Symptoms were also more prevalent in houses with a high U value, reflecting a poor thermal insulation. Compared to natural ventilation, living in a house with mechanical supply and exhaust ventilation was related to a lower prevalence of general symptoms and any SBS symptoms, but there were only weak associations between measured air exchange rate and symptoms. CONCLUSIONS: A large proportion of single-family houses have dampness problems in the foundation, and pollutants may enter the living space of the house and affect the health of the occupants. Furthermore, absolute air humidity should be measured more often in indoor air studies.


Subject(s)
Humidity , Sick Building Syndrome/epidemiology , Ventilation/statistics & numerical data , Adult , Age Factors , Female , Humans , Logistic Models , Male , Middle Aged , Sex Factors , Sweden/epidemiology
6.
Proc Natl Acad Sci U S A ; 110(39): 15561-6, 2013 Sep 24.
Article in English | MEDLINE | ID: mdl-24023065

ABSTRACT

The assignment of the two substrate water sites of the tetra-manganese penta-oxygen calcium (Mn4O5Ca) cluster of photosystem II is essential for the elucidation of the mechanism of biological O-O bond formation and the subsequent design of bio-inspired water-splitting catalysts. We recently demonstrated using pulsed EPR spectroscopy that one of the five oxygen bridges (µ-oxo) exchanges unusually rapidly with bulk water and is thus a likely candidate for one of the substrates. Ammonia, a water analog, was previously shown to bind to the Mn4O5Ca cluster, potentially displacing a water/substrate ligand [Britt RD, et al. (1989) J Am Chem Soc 111(10):3522-3532]. Here we show by a combination of EPR and time-resolved membrane inlet mass spectrometry that the binding of ammonia perturbs the exchangeable µ-oxo bridge without drastically altering the binding/exchange kinetics of the two substrates. In combination with broken-symmetry density functional theory, our results show that (i) the exchangable µ-oxo bridge is O5 {using the labeling of the current crystal structure [Umena Y, et al. (2011) Nature 473(7345):55-60]}; (ii) ammonia displaces a water ligand to the outer manganese (MnA4-W1); and (iii) as W1 is trans to O5, ammonia binding elongates the MnA4-O5 bond, leading to the perturbation of the µ-oxo bridge resonance and to a small change in the water exchange rates. These experimental results support O-O bond formation between O5 and possibly an oxyl radical as proposed by Siegbahn and exclude W1 as the second substrate water.


Subject(s)
Ammonia/metabolism , Manganese/metabolism , Oxygen/metabolism , Photosystem II Protein Complex/metabolism , Solvents/metabolism , Electrons , Ligands , Magnetic Resonance Spectroscopy , Photosystem II Protein Complex/chemistry , Spin Labels , Water
7.
Biochim Biophys Acta ; 1837(8): 1257-62, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24726350

ABSTRACT

The binding affinity of the two substrate-water molecules to the water-oxidizing Mn4CaO5 catalyst in photosystem II core complexes of the extremophilic red alga Cyanidioschyzon merolae was studied in the S2 and S3 states by the exchange of bound ¹6O-substrate against ¹8O-labeled water. The rate of this exchange was detected via the membrane-inlet mass spectrometric analysis of flash-induced oxygen evolution. For both redox states a fast and slow phase of water-exchange was resolved at the mixed labeled m/z 34 mass peak: kf=52 ± 8s⁻¹ and ks=1.9 ± 0.3s⁻¹ in the S2 state, and kf=42 ± 2s⁻¹ and kslow=1.2 ± 0.3s⁻¹ in S3, respectively. Overall these exchange rates are similar to those observed previously with preparations of other organisms. The most remarkable finding is a significantly slower exchange at the fast substrate-water site in the S2 state, which confirms beyond doubt that both substrate-water molecules are already bound in the S2 state. This leads to a very small change of the affinity for both the fast and the slowly exchanging substrates during the S2→S3 transition. Implications for recent models for water-oxidation are briefly discussed.


Subject(s)
Oxidation-Reduction , Photosystem II Protein Complex/chemistry , Rhodophyta/growth & development , Water/chemistry , Binding Sites , Catalysis , Kinetics , Manganese/chemistry , Oxygen/chemistry , Photosystem II Protein Complex/genetics , Rhodophyta/chemistry , Rhodophyta/genetics , Substrate Specificity
8.
J Holist Nurs ; 40(1): 64-73, 2022 Mar.
Article in English | MEDLINE | ID: mdl-34287073

ABSTRACT

Among all the groups and occupations that have been affected by the global pandemic, nursing professionals stand out as having been particularly hard-pressed due to the dramatic increase in the need for their services. Given the rising tide of coronavirus disease 2019 patients who require specialized medical treatment as well as the millions of others that are lining up for vaccinations, it can be assumed that many nursing professionals have had to endure such things as longer working hours, tighter schedules, and the intensity of a work environment in which failure of care and multiple deaths are the daily fare. This article proposes that nurses can avoid such severe consequences by taking up a regime of enhanced self-care management that enables them to achieve psychophysical balance and wellness. Three practices are highlighted in this regard: prayer, meditative walking, and the mindfulness practice of body scanning. Our suggestion is that these coping strategies will be both beneficial and healthful for nursing professionals in terms of enhancing their spiritual/existential resilience and meeting their own need for consolation as they navigate in an extremely difficult and demanding work environment.


Subject(s)
COVID-19 , Holistic Nursing , Nursing Care , Adaptation, Psychological , Humans , SARS-CoV-2 , Self Care
9.
J Oral Rehabil ; 38(10): 713-21, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21434963

ABSTRACT

The aim was to investigate long-term efficacy of a resilient appliance in patients with pain due to temporomandibular disorders (TMD). A randomised, controlled trial was performed in 80 recruited TMD pain patients. They were randomly allocated to one of two groups: treatment with a resilient appliance or treatment with a hard, palatal, non-occluding appliance. The primary treatment outcome was judged positive when patients' characteristic pain intensity decreased by at least 30%. Additional treatment outcomes were physical functioning, emotional functioning and headache. At the 12-month follow-up 50% of the patients in the treatment group and 42% in the control group had a 30% reduction of characteristic pain intensity, when calculated in an intent-to-treat analysis. Jaw function improved in both groups at the 6- and 12-month follow-up. Emotional functioning improved in both groups at the 6-month follow-up; an improvement concerning grade of depression was found in the control group at 12 months. Headache decreased in both groups at both follow-ups. There were no statistically significant differences found regarding primary and additional outcomes between groups at the 6- and 12-months follow-up. There was no statistically significant difference between the resilient appliance and the non-occluding control appliance in reducing TMD pain, physical functioning, emotional functioning and headache in a 12 months perspective.


Subject(s)
Arthralgia/therapy , Facial Pain/therapy , Occlusal Splints , Orthodontic Appliance Design , Temporomandibular Joint Disorders/therapy , Adult , Arthralgia/physiopathology , Arthralgia/psychology , Depression/etiology , Depression/prevention & control , Facial Pain/physiopathology , Facial Pain/psychology , Female , Follow-Up Studies , Headache/etiology , Headache/prevention & control , Humans , Jaw/physiopathology , Male , Pain Measurement , Temporomandibular Joint/physiopathology , Temporomandibular Joint Disorders/physiopathology , Temporomandibular Joint Disorders/psychology , Time Factors , Treatment Outcome
10.
Psychol Rev ; 128(6): 1088-1111, 2021 11.
Article in English | MEDLINE | ID: mdl-34292023

ABSTRACT

People often take nondiagnostic information into account when revising their beliefs. A probability judgment decreases due to nondiagnostic information represents the well-established "dilution effect" observed in many domains. Surprisingly, the opposite of the dilution effect called the "confirmation effect" has also been observed frequently. The present work provides a unified cognitive model that allows both effects to be explained simultaneously. The suggested similarity-updating model incorporates two psychological components: first, a similarity-based judgment inspired by categorization research, and second, a weighting-and-adding process with an adjustment following a similarity-based confirmation mechanism. Four experimental studies demonstrate the model's predictive accuracy for probability judgments and belief revision. The participants received a sample of information from one of two options and had to judge from which option the information came. The similarity-updating model predicts that the probability judgment is a function of the similarity of the sample to the options. When one is presented with a new sample, the previous probability judgment is updated with a second probability judgment by taking a weighted average of the two and adjusting the result according to a similarity-based confirmation. The model describes people's probability judgments well and outcompetes a Bayesian cognitive model and an alternative probability-theory-plus-noise model. The similarity-updating model accounts for several qualitative findings, namely, dilution effects, confirmation effects, order effects, and the finding that probability judgments are invariant to sample size. In sum, the similarity-updating model provides a plausible account of human probability judgment and belief revision. (PsycInfo Database Record (c) 2021 APA, all rights reserved).


Subject(s)
Judgment , Probability Theory , Bayes Theorem , Humans , Probability
11.
Acta Odontol Scand ; 68(3): 141-7, 2010 May.
Article in English | MEDLINE | ID: mdl-20113145

ABSTRACT

OBJECTIVES: To study how sense of coherence (SOC), grade of depression and non-specific physical symptoms and general health influence the efficacy of intraoral appliance therapy in patients with temporomandibular disorder (TMD) pain. A second objective was to study the association between SOC, grade of depression, grade of non-specific physical symptoms and general health. MATERIAL AND METHODS: A total of 73 TMD pain patients participated; 36 were treated with a resilient appliance and 37 with a non-occluding control appliance in a randomized controlled trial for a period of 10 weeks. All patients had at least one pain diagnosis according to the research diagnostic criteria for TMD, including both the Symptom Checklist-90-Revised (Axis II) measuring grade of depression and non-specific physical symptoms, and general health (physical characteristics). Patients also filled in the 29-item SOC questionnaire. RESULTS: A low grade of SOC was found in eight of the patients in the treatment group and in 17 of the control group at baseline, with a statistically significant difference between the groups. Logistic regression analyses revealed that, after correcting for the background variables, the resilient appliance did not differ from the non-occluding control appliance in terms of treatment outcome. No statistically significant differences were found when correlating mean SOC with grade of depression, grade of non-specific physical symptoms and general health. CONCLUSIONS: These findings indicate that none of the studied background variables (age, gender, SOC, depression, non-specific physical symptoms or general health) seemed to influence the short-term efficacy of intraoral appliances. No association was found between SOC and depression, non-specific physical symptoms or general health in TMD pain patients.


Subject(s)
Depression/complications , Facial Pain/psychology , Occlusal Splints , Sense of Coherence , Temporomandibular Joint Disorders/psychology , Temporomandibular Joint Disorders/therapy , Adult , Age Factors , Analysis of Variance , Arthralgia/etiology , Arthralgia/psychology , Facial Pain/etiology , Female , Health Status , Humans , Logistic Models , Male , Sex Factors , Single-Blind Method , Surveys and Questionnaires , Temporomandibular Joint Disorders/complications , Young Adult
12.
Swed Dent J Suppl ; (206): 9-88, 2010.
Article in English | MEDLINE | ID: mdl-20626187

ABSTRACT

Temporomandibular disorders (TMD) with orofacial pain with or without reduced jaw function, are frequent conditions in the general population. Different factors such as tooth clenching and grinding, sometimes due to enhanced psychosocial stress, and trauma to the jaws may be important as etiologic factors. Signs and symptoms of TMD are a common cause for general practitioners to use different intraoral appliances as pain and bite-force reducing devices and for improvement of a reduced jaw function. Intraoral appliances are often used parallel to other treatment modalities. Before treatment start a thorough history taking and clinical examination is necessary for a relevant diagnosis. Sometimes the diagnostic process has to be complemented with proper radiographic imaging in order to support the diagnostic process. The overall aim of this thesis was to compare magnetic resonance imaging (MRI) findings of the TMJ on the clinically assessed diagnoses and to evaluate short- and long-term treatment outcome of a resilient intraoral appliance, in patients with TMD pain. A further aim was to study Sense of Coherence as an influencing factor on treatment outcome, on these patients. In article I the aim was to compare findings on MRI in TMD pain patients with clinical diagnoses of myofascial pain or arthralgia/osteoarthritis in combination with myofascial pain according to the Research Diagnostic Criteria for TMD (RDC/TMD). The temporomandibular joints of 60 consecutive patients, 19 with myofascial pain and 41 patients with arthralgia/osteoarthritis in combination with myofascial pain were examined clinically and with MRI. The most common MRI findings were disc displacements with or without reduction and structural bone changes. These findings were found in both pain groups, however, disc displacements were found significantly more often in patients with arthralgia/osteoarthritis in combination with myofascial pain. Joint fluid was found in both pain groups. The clinical diagnoses for subdivision into myogenous only or combined arthrogenous and myogenous pain groups were not confirmed by MRI findings. In article II the short-term efficacy of a resilient appliance compared to a non-occluding control appliance was studied in a randomised, controlled trial with 80 recruited TMD pain patients. They were randomly allocated to one of two groups: treatment with a resilient appliance or treatment with a hard, palatal, nonoccluding appliance. After 6 and 10 weeks of treatment, characteristic pain intensity (CPI) decreased in both groups. There was no statistically significant difference found between the resilient appliance and the non-occluding control appliance in reducing TMD pain in a short-term perspective. In article III possible factors of importance for treatment outcome were studied as well as the association between Sense of Coherence and grade of depression, and grade of non-specific physical symptoms and general health, in the TMD pain patients. A total of 73 TMD pain patients participated; 36 were treated with a resilient appliance and 37 with a non-occluding control appliance. The findings indicated that none of the studied background variables (age, gender, SoC, depression, nonspecific physical symptoms or general health) seemed to influence the short-term efficacy of intraoral appliances. In the TMD pain patients, no associations were found between SoC and depression, non-specific physical symptoms or general health. In article IV the long-term efficacy was evaluated of the resilient appliance compared to the non-occluding control appliance in the TMD pain patients. Appliance wear was also studied in this article. As in the short-term follow-up, there was no statistically significant difference between the resilient appliance and the non-occluding control appliance in reducing TMD pain in the long-term perspective.


Subject(s)
Temporomandibular Joint Disorders/therapy , Adaptation, Psychological , Arthralgia/complications , Arthralgia/diagnosis , Depression/diagnosis , Facial Pain/diagnosis , Humans , Joint Dislocations/diagnosis , Magnetic Resonance Imaging , Occlusal Splints , Orthodontic Appliance Design , Osteoarthritis/complications , Osteoarthritis/diagnosis , Temporomandibular Joint Disc/pathology , Temporomandibular Joint Disorders/diagnosis , Temporomandibular Joint Disorders/psychology , Treatment Outcome
13.
J Rheumatol ; 47(5): 730-738, 2020 05 01.
Article in English | MEDLINE | ID: mdl-31523047

ABSTRACT

OBJECTIVE: To determine the prevalence of orofacial symptoms, dysfunctions, and deformities of the temporomandibular joint (TMJ) in juvenile idiopathic arthritis (JIA) 17 years after disease onset. METHODS: Drawn from a prospective, population-based Nordic JIA cohort with disease onset from 1997 to 2000, 420 consecutive cases were eligible for orofacial evaluation of TMJ involvement. The followup visit included demographic data, a standardized clinical orofacial examination, and full-face cone-beam computed tomography (CBCT). For comparison, 200 age-matched healthy controls were used. RESULTS: Of 420 eligible participants with JIA, 265 (63%) were included (mean age 23.5 ± 4.2 yrs) and completed a standardized clinical orofacial examination. Of these, 245 had a full-face CBCT performed. At least 1 orofacial symptom was reported by 33%. Compared to controls, the JIA group significantly more often reported TMJ pain, TMJ morning stiffness, and limitation on chewing. Further, among participants reporting complaints, the number of symptoms was also higher in JIA. The mean maximal incisal opening was lower in the JIA group (p < 0.001), and TMJ pain on palpation was more frequent. Condylar deformities and/or erosions were observed in 61% as assessed by CBCT, showing bilateral changes in about 70%. Risk factors of condylar deformities were orofacial dysfunction or biologic treatment; enthesitis-related arthritis was protective. CONCLUSION: This study of the longterm consequences of TMJ involvement in a population-based JIA cohort reports persistence of comprehensive symptoms, dysfunctions, and damage of the TMJ into adulthood. We suggest interdisciplinary followup of JIA patients also in adulthood.


Subject(s)
Arthritis, Juvenile , Temporomandibular Joint Disorders , Adult , Arthritis, Juvenile/complications , Cohort Studies , Humans , Prospective Studies , Temporomandibular Joint , Temporomandibular Joint Disorders/complications , Young Adult
14.
Psychol Rev ; 116(4): 856-74, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19839686

ABSTRACT

Probability theory has long been taken as the self-evident norm against which to evaluate inductive reasoning, and classical demonstrations of violations of this norm include the conjunction error and base-rate neglect. Many of these phenomena require multiplicative probability integration, whereas people seem more inclined to linear additive integration, in part, at least, because of well-known capacity constraints on controlled thought. In this article, the authors show with computer simulations that when based on approximate knowledge of probabilities, as is routinely the case in natural environments, linear additive integration can yield as accurate estimates, and as good average decision returns, as estimates based on probability theory. It is proposed that in natural environments people have little opportunity or incentive to induce the normative rules of probability theory and, given their cognitive constraints, linear additive integration may often offer superior bounded rationality.


Subject(s)
Computer Simulation , Probability Theory , Problem Solving , Bayes Theorem , Decision Making , Decision Theory , Humans , Judgment , Linear Models
15.
Eur Biophys J ; 38(2): 245-54, 2009 Feb.
Article in English | MEDLINE | ID: mdl-18923826

ABSTRACT

Detailed analyses of the mechanisms that mediate binding of the uropathogenic Escherichia coli to host cells are essential, as attachment is a prerequisite for the subsequent infection process. We explore, by means of force measuring optical tweezers, the interaction between the galabiose receptor and the adhesin PapG expressed by P pili on single bacterial cells. Two variants of dynamic force spectroscopy were applied based on constant and non-linear loading force. The specific PapG-galabiose binding showed typical slip-bond behaviour in the force interval (30-100 pN) set by the pilus intrinsic biomechanical properties. Moreover, it was found that the bond has a thermodynamic off-rate and a bond length of 2.6 x 10(-3) s(-1) and 5.0 A, respectively. Consequently, the PapG-galabiose complex is significantly stronger than the internal bonds in the P pilus structure that stabilizes the helical chain-like macromolecule. This finding suggests that the specific binding is strong enough to enable the P pili rod to unfold when subjected to strong shear forces in the urinary tract. The unfolding process of the P pili rod promotes the formation of strong multipili interaction, which is important for the bacterium to maintain attachment to the host cells.


Subject(s)
Adhesins, Escherichia coli/metabolism , Bacterial Adhesion/physiology , Disaccharides/metabolism , Fimbriae Proteins/metabolism , Fimbriae, Bacterial/physiology , Adhesins, Escherichia coli/chemistry , Disaccharides/chemistry , Escherichia coli/cytology , Escherichia coli/physiology , Fimbriae Proteins/chemistry , Fimbriae, Bacterial/chemistry , Microscopy, Atomic Force , Models, Biological , Optical Tweezers , Protein Binding/physiology , Tensile Strength/physiology
16.
Cranio ; 27(3): 185-93, 2009 Jul.
Article in English | MEDLINE | ID: mdl-19697647

ABSTRACT

The aim of this research was to study if changes in condyle position in temporomandibular disorders (TMD) patients could be a factor that is affected by resilient appliance therapy and if it influences the treatment outcome. The study investigated 48 patients randomly assigned to a treatment group (T group = 21 patients, using resilient appliance) or a control group (C group = 27 patients, using nonoccluding appliance). Changes in the condyle-fossa relationship (with and without the appliance) were determined in an MRI examination. Ten weeks after treatment, the treatment outcome was measured. The results showed that with the appliance, change in condyle position occurred in 76% of the T group and 22% of the C group (p < 0.001). Sixty-seven percent (67%) of the T group and 44% of the C group experienced a successful treatment outcome. Treatment outcome was not related to changes in condyle position in patients with TMD pain.


Subject(s)
Facial Pain/therapy , Mandibular Condyle/pathology , Occlusal Splints , Temporomandibular Joint Disc/pathology , Temporomandibular Joint Disorders/therapy , Adolescent , Adult , Centric Relation , Facial Pain/complications , Facial Pain/pathology , Female , Humans , Magnetic Resonance Imaging , Male , Mandibular Condyle/diagnostic imaging , Middle Aged , Orthodontic Appliance Design , Radiography , Range of Motion, Articular , Temporomandibular Joint Disc/diagnostic imaging , Temporomandibular Joint Disorders/complications , Temporomandibular Joint Disorders/pathology , Treatment Outcome , Young Adult
17.
Swed Dent J ; 32(1): 9-16, 2008.
Article in English | MEDLINE | ID: mdl-18540516

ABSTRACT

The aim of this study was to evaluate the treatment effect of a combined treatment with a stabilisation appliance and a soft appliance in the opposing jaw in patients refractory to previous TMD treatment. During a 5-year-period, 2001-2005, a total of 98 patients received the combined treatment at the Department of Stomatognathic Physiology, the Institute for Postgraduate Dental Education, Jönköping, Sweden. Before the patients received the combined treatment, they had already been given several different TMD treatments during a long period of time, either before referral or at the specialist clinic, with only minor or no effect on their TMD symptoms. The patients were followed prospectively (n=10), or analysed retrospectively (n=88). The data registered were gender, age, main indication for TMD treatment, number of visits to the clinic before and after the introduction of the combined treatment, as well as according to a clinical (Di) and anamnestic (Ai) dysfunction index. The most common causes for treatment in the retrospective material were problems of muscular origin and problems of both muscular and TMJ origin. In the prospective material, most of the patients had mainly muscular symptoms. Both the clinical and anamnestic dysfunction index decreased statistically significantly in the retrospective material after the introduction of the combined treatment. There was a numerical improvement of both indices also in the prospective material. In conclusion, the present investigation showed that a combined treatment with a hard acrylic stabilisation appliance and a soft appliance in the opposing jaw seems to give a remarkable improvement of TMD signs and symptoms in apparently therapy resistant TMD patients. General conclusions should, however, be made with caution due to the fact that the study did not include any control group. There is an obvious need for randomized controlled studies concerning the efficacy and effectiveness of the combined treatment presented in this study.


Subject(s)
Occlusal Splints , Temporomandibular Joint Disorders/therapy , Acrylic Resins , Adolescent , Adult , Aged , Combined Modality Therapy , Female , Humans , Male , Middle Aged , Orthodontic Appliance Design , Outcome Assessment, Health Care , Prospective Studies , Retrospective Studies , Temporomandibular Joint Disorders/diagnosis , Temporomandibular Joint Dysfunction Syndrome/diagnosis , Temporomandibular Joint Dysfunction Syndrome/therapy
18.
J Biomech ; 76: 16-26, 2018 07 25.
Article in English | MEDLINE | ID: mdl-29801662

ABSTRACT

The dorsal root ganglion (DRG) that is embedded in the foramen of the cervical vertebra can be injured during a whiplash motion. A potential cause is that whilst the neck bends in the whiplash motion, the changes of spinal canal volume induce impulsive pressure transients in the venous blood outside the dura mater (DM) and in the cerebrospinal fluid (CSF) inside the DM. The fluids can dynamically interact with the DRG and DM, which are deformable. In this work, the interaction is investigated numerically using a strong-coupling partitioned method that synchronize the computations of the fluid and structure. It is found that the interaction includes two basic processes, i.e., the pulling and pressing processes. In the pulling process, the DRG is stretched towards the spinal canal, and the venous blood is driven into the canal via the foramen. This process results from negative pressure in the fluids. In contrast, the pressing process is caused by positive pressure that leads to compression of the DRG and the outflow of the venous blood from the canal. The largest pressure gradient is observed at the foramen, where the DRG is located at. The DRG is subject to prominent von Mises stress near its end, which is fixed without motions. The negative internal pressure is more efficient to deform the DRG than the positive internal pressure. This indicates that the most hazardous condition for the DRG is the pulling process.


Subject(s)
Blood Pressure/physiology , Cerebrospinal Fluid Pressure/physiology , Cervical Vertebrae/physiology , Ganglia, Spinal/physiology , Whiplash Injuries/physiopathology , Humans , Neck/physiology , Spinal Canal/physiology
19.
Psychol Rev ; 123(1): 103-11, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26709414

ABSTRACT

Costello and Watts (2014) present a model assuming that people's knowledge of probabilities adheres to probability theory, but that their probability judgments are perturbed by a random noise in the retrieval from memory. Predictions for the relationships between probability judgments for constituent events and their disjunctions and conjunctions, as well as for sums of such judgments were derived from probability theory. Costello and Watts (2014) report behavioral data showing that subjective probability judgments accord with these predictions. Based on the finding that subjective probability judgments follow probability theory, Costello and Watts (2014) conclude that the results imply that people's probability judgments embody the rules of probability theory and thereby refute theories of heuristic processing. Here, we demonstrate the invalidity of this conclusion by showing that all of the tested predictions follow straightforwardly from an account assuming heuristic probability integration (Nilsson, Winman, Juslin, & Hansson, 2009). We end with a discussion of a number of previous findings that harmonize very poorly with the predictions by the model suggested by Costello and Watts (2014).


Subject(s)
Judgment/physiology , Models, Theoretical , Probability Theory , Humans
20.
J Biomech ; 49(3): 416-22, 2016 Feb 08.
Article in English | MEDLINE | ID: mdl-26827171

ABSTRACT

In vehicle collisions, the occupant's torso is accelerated in a given direction while the unsupported head tends to lag behind. This mechanism results in whiplash motion to the neck. In whiplash experiments conducted for animals, pressure transients have been recorded in the spinal canal. It was hypothesized that the transients caused dorsal root ganglion dysfunction. Neck motion introduces volume changes inside the vertebral canal. The changes require an adaptation which is likely achieved by redistribution of blood volume in the internal vertebral venous plexus (IVVP). Pressure transients then arise from the rapid redistribution. The present study aimed to explore the hypothesis theoretically and analytically. Further, the objectives were to quantify the effect of the neck motion on the pressure generation and to identify the physical factors involved. We developed a hydrodynamic system of tubes that represent the IVVP and its lateral intervertebral vein connections. An analytical model was developed for an anatomical geometrical relation that the venous blood volume changes with respect to the vertebral angular displacement. This model was adopted in the hydrodynamic tube system so that the system can predict the pressure transients on the basis of the neck vertebral motion data from a whiplash experiment. The predicted pressure transients were in good agreement with the earlier experimental data. A parametric study was conducted and showed that the system can be used to assess the influences of anatomical geometrical properties and vehicle collision severity on the pressure generation.


Subject(s)
Hydrodynamics , Motion , Whiplash Injuries/physiopathology , Head/physiopathology , Humans , Models, Biological , Neck/physiopathology , Pressure , Spinal Canal/physiopathology , Spine/physiopathology , Veins
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